Exelon Generation—owner and operator of the nation’s largest power reactor fleet—held an online event yesterday outlining the company’s business strategy as it prepares to separate from Exelon Corporation under the name Constellation. The separation is expected to become final on February 1.

When a nuclear power plant closes, here is what happens:

Thousands of people lose their jobs. The local economy nosedives. Air pollution increases. Reliance on natural gas, often bought from out-of-state, goes up. Electricity on the grid becomes less reliable with the loss of the most reliable source of power. And electric prices can even rise.